Gehu Lake is a macrophyte type shallow lake located in the Taihu Lake groups in the southeast plain to Changzhou City, Jiangsu Provence, with an area of 164 km², and an average depth of 1.26m.The nutrient balance results show: (1) The total nutrients inputted are N 4120.29 t/a and P 270.03t/a, coming separately from its inlets(N 2961.86t/a, P 154.38t/a), land around the lake(N 45.83t/a, P 1.46t/a),cage aquaculture and artifitial food (N 509, 95t/a, P 80.60t/a), released sediments (N 362.20 t/a, P 19.16t/a) and atmospheric precipitation (N 240.45 t/a, P 14.43t,/a).The total nutrients drained are N 2632.9 It/a and P 175.21 t/a, outflowing through rivers (N 2172.llt/a,P 77.03t/a),harvest of fish (N 230.64t/a,P 59.66t/a),harvest of aquatic plants (N 210.OOt/a.P 37.80t/a)? irrigation and factory utilization around the lake (N 20.16t/a, P 0.72t/a).The N deposits 1487.38t/a(deposit efficient 0.361) and the P deposits 94.82t/a (deposit cofficient 0.3511).The main input and output ways of N and P are rivers.The input N by rivers occupies 71.88% of total input and P 57.17%. (2) Nutrient load is much higher, N is 25.12g/(m²·a) and P 1.647g/(m²·a). (3) The amount of nutrients released from the sediments of the cage aquaculture region is great.The daily releasing of N is 14.3 mg/m² and P 0.65mg/m².